oj.uz

Submission #981222

# Submission time Handle Problem Language Result Execution time Memory
981222 2024-05-13T02:34:29 Z Lib Swapping Cities (APIO20_swap) C++14
7 / 100
 315 ms 63924 KB 
#include <bits/stdc++.h>
using namespace std;
int n,m;
vector <vector <int> > InComponents;
vector <vector <int> > adj; //the edge list of the KRT
vector <int> TVector;
int RootID; //ID of the root node of the KRT;
struct Edge{
	long long Weight;
	int Start;
	int End;
};
bool operator< (const Edge &x, const Edge &y){
	return x.Weight<y.Weight;
}
Edge Elist[500003];
int Depth[500003];
int Deg[500003];
int CurRep[500003]; //id of the respresentative node on the KRT
int Par[500003]; //Parent of node with id i on the KRT;
int Toggle[500003]; //is the i-th node on the KRT toggled?
int Check[500003];
int Ancestor[500003][20];
long long Val[500003];//the value of the i-th node of the KRT
vector <int> KRTID;
void DSU(int id, int u, int v, int w){
	Deg[u]++;
	Deg[v]++;
	//u and v belongs to the same component. The component now has a cycle. Immediately toggle the root node of the current 
	//subtree that includes both u and v on the KRT
	if(CurRep[u]==CurRep[v]){
		//The node isn't toggled just yet. Toggle it immediately
		if(!Toggle[CurRep[u]]){
			Toggle[CurRep[u]]=1;
			Val[CurRep[u]]=w;
		}else{
		//The node is already toggled by an edge with lower edge. Only a fucking dumbass would touch it - already minimized
		//toggle value. Just leave it alone
		}
	}else{
		//u and v doesn't belong to the same component. Merge them
		int CurID=n-1+id;
		int OldComp1=CurRep[u], OldComp2=CurRep[v];
		adj[CurRep[u]].push_back(CurID);
		adj[CurRep[v]].push_back(CurID);
		adj[CurID].push_back(CurRep[u]);
		adj[CurID].push_back(CurRep[v]);
		Par[CurRep[u]]=CurID;
		Par[CurRep[v]]=CurID;
		if(InComponents[u].size()>InComponents[v].size()){
			swap(u,v);
			//Small to large merging
		}
		for(int i=0;i<InComponents[u].size();i++){
			InComponents[CurID].push_back(InComponents[u][i]);
			CurRep[InComponents[u][i]]=CurID;
		}
		for(int i=0;i<InComponents[v].size();i++){
			InComponents[CurID].push_back(InComponents[v][i]);
			CurRep[InComponents[v][i]]=CurID;
		}
		Val[CurID]=w;
		//if either of the components are toggled already (having a cycle OR a vertex with degree >3)
		//OR the merged component has a vertex with degree >3 (either u or v), toggle immediately
		if(Toggle[OldComp1]||Toggle[OldComp2]||Deg[u]>2||Deg[v]>2){
			Toggle[CurID]=1;
		}
		KRTID.push_back(CurID);
		RootID=CurID;
	}
}
void init(int N, int M, vector <int> U, vector <int> V, vector <int> W){
	n=N;
	m=M;
	for(int i=0;i<n+m+5;i++){
		InComponents.push_back(TVector);
		adj.push_back(TVector);
	}
	for(int i=1;i<=m;i++){
		Elist[i].Weight=W[i-1];
		Elist[i].Start=U[i-1];
		Elist[i].End=V[i-1];
	}
	sort(Elist+1,Elist+m+1);
	for(int i=0;i<n;i++){
		CurRep[i]=i;
		InComponents[i].push_back(i);
		KRTID.push_back(i);
	}
	for(int i=1;i<=m;i++){
		DSU(i,Elist[i].Start,Elist[i].End,Elist[i].Weight);
	}
	//The KRT is now built. BFS from the root node and initialize LCA or something
	deque <int> dq;
	dq.push_back(RootID);
	Check[RootID]=1;
	int Cur;
	while(!dq.empty()){
		Cur=dq.front();
		for(int i=0;i<adj[Cur].size();i++){
			if(!Check[adj[Cur][i]]){
				dq.push_back(adj[Cur][i]);
				Check[adj[Cur][i]]=1;
				Depth[adj[Cur][i]]=Depth[Cur]+1;
			}
		}
		dq.pop_front();
	}
	Par[RootID]=500000;
	Par[500000]=500000;
	Toggle[500000]=1;
	for(int i=0;i<=19;i++){
		for(int k=0;k<KRTID.size();k++){
			if(i==0){
				Ancestor[KRTID[k]][i]=Par[KRTID[k]];
			}else{
				Ancestor[KRTID[k]][i]=Ancestor[Ancestor[KRTID[k]][i-1]][i-1];
			}
		}
	}
}

int getMinimumFuelCapacity(int x, int y){
	//I thought that we actually need to use binary lifting to find LCA and then jump from the LCA to find the nearest
	//toggled node on the KRT
	//But apparently small-to-large merging ensures that the depth of the tree is always logN or something, so bruteforcing
	//it is
	//ok nvm this guy is a fucking moron lmao LogN depth my ass. Wrong analysis, wasted 5 minutes. Fuck me
	if(Depth[x]<Depth[y]){
		swap(x,y);
	}
	int JumpLevel=Depth[x]-Depth[y];
	for(int i=19;i>=0;i--){
		if(JumpLevel >> i & 1){
			x=Ancestor[x][i];
		}
	}
	for(int i=19;i>=0;i--){
		if(Ancestor[x][i]!=Ancestor[y][i]){
			x=Ancestor[x][i];
			y=Ancestor[y][i];
		}
	}
	x=Par[x];
	y=Par[y];
	SkipPoint:;
	if(Toggle[x]){
		return Val[x];
	}
	/*int cnt=0;
	while(!Toggle[Par[x]]&&Par[x]!=500000){
		x=Par[x];
	}*/
	for(int i=19;i>=0;i--){
		if(!Toggle[Ancestor[x][i]]){
			x=Ancestor[x][i];
		}
	}
	x=Par[x];
	if(Toggle[x]&&x!=500000){
		return Val[x];
	}
	return -1;
}

Compilation message

swap.cpp: In function 'void DSU(int, int, int, int)':
swap.cpp:54:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |   for(int i=0;i<InComponents[u].size();i++){
      |               ~^~~~~~~~~~~~~~~~~~~~~~~
swap.cpp:58:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |   for(int i=0;i<InComponents[v].size();i++){
      |               ~^~~~~~~~~~~~~~~~~~~~~~~
swap.cpp: In function 'void init(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
swap.cpp:100:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |   for(int i=0;i<adj[Cur].size();i++){
      |               ~^~~~~~~~~~~~~~~~
swap.cpp:113:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  113 |   for(int k=0;k<KRTID.size();k++){
      |               ~^~~~~~~~~~~~~
swap.cpp: In function 'int getMinimumFuelCapacity(int, int)':
swap.cpp:146:2: warning: label 'SkipPoint' defined but not used [-Wunused-label]
  146 |  SkipPoint:;
      |  ^~~~~~~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12632 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 2 ms 12632 KB Output is correct
4 Correct 2 ms 12632 KB Output is correct
5 Correct 2 ms 12888 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 2 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 90 ms 49016 KB Output is correct
10 Correct 126 ms 60800 KB Output is correct
11 Correct 134 ms 59124 KB Output is correct
12 Correct 153 ms 60144 KB Output is correct
13 Correct 110 ms 59636 KB Output is correct
14 Correct 100 ms 50988 KB Output is correct
15 Correct 233 ms 62636 KB Output is correct
16 Correct 225 ms 60836 KB Output is correct
17 Correct 255 ms 62088 KB Output is correct
18 Correct 315 ms 61168 KB Output is correct
19 Incorrect 82 ms 25172 KB Output isn't correct
20 Halted 0 ms 0 KB -

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12632 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 200 ms 63732 KB Output is correct
4 Correct 242 ms 61884 KB Output is correct
5 Correct 189 ms 62644 KB Output is correct
6 Correct 185 ms 63924 KB Output is correct
7 Correct 189 ms 62600 KB Output is correct
8 Correct 189 ms 60048 KB Output is correct
9 Correct 240 ms 62976 KB Output is correct
10 Correct 225 ms 60892 KB Output is correct

Subtask #3
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12632 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 2 ms 12632 KB Output is correct
4 Correct 2 ms 12632 KB Output is correct
5 Correct 2 ms 12888 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 2 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Incorrect 2 ms 12632 KB Output isn't correct
10 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 12632 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12632 KB Output is correct
2 Correct 2 ms 12636 KB Output is correct
3 Correct 2 ms 12632 KB Output is correct
4 Correct 2 ms 12632 KB Output is correct
5 Correct 2 ms 12888 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 2 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 90 ms 49016 KB Output is correct
10 Correct 126 ms 60800 KB Output is correct
11 Correct 134 ms 59124 KB Output is correct
12 Correct 153 ms 60144 KB Output is correct
13 Correct 110 ms 59636 KB Output is correct
14 Correct 100 ms 50988 KB Output is correct
15 Correct 233 ms 62636 KB Output is correct
16 Correct 225 ms 60836 KB Output is correct
17 Correct 255 ms 62088 KB Output is correct
18 Correct 315 ms 61168 KB Output is correct
19 Correct 200 ms 63732 KB Output is correct
20 Correct 242 ms 61884 KB Output is correct
21 Correct 189 ms 62644 KB Output is correct
22 Correct 185 ms 63924 KB Output is correct
23 Correct 189 ms 62600 KB Output is correct
24 Correct 189 ms 60048 KB Output is correct
25 Correct 240 ms 62976 KB Output is correct
26 Correct 225 ms 60892 KB Output is correct
27 Incorrect 2 ms 12888 KB Output isn't correct
28 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 12632 KB Output isn't correct
2 Halted 0 ms 0 KB -